list1 = ['physics', 'chemistry', 1997, 2000]
list2 = [1, 2, 3, 4, 5]
list3 = ["a", "b", "c", "d"]
print(list1[0])
print(list2[2])
print(list3[3])
print(list3[2:4])
list3.append("e")
print(list3)
del list3[0]
print(list3)
print(len(list1))
